Numerous polymer-based medical devices have been developed for the delivery of therapeutic agents to the body. The desired release profile for the therapeutic agent is dependent upon the particular treatment at hand, including the specific condition being treated or prevented, the specific site of administration, the specific therapeutic agent selected, and so forth.
In accordance with some typical delivery strategies, a therapeutic agent is provided within a polymeric carrier layer and/or beneath a polymeric barrier layer that is associated with a medical device. Once the medical device is placed at the desired location within a patient, the therapeutic agent is released from the medical device at a rate that is dependent upon the nature of the polymeric carrier and/or barrier layer.
Although controlled release of a therapeutic agent by means of polymeric materials has existed in various forms for several years, there is a continuing need for improved and more precise drug delivery systems, including polymer-containing materials, whose release characteristics may be readily modulated depending on the required need.